Reinforced concrete for marine foundations.



1 R. FERGUSON.

REINFORCED CONCRETE FOR MARINE FOUNDATIONS.

APPUcATloN FILED r11/111.1111917.

ljqgl. j-9.4.

destructive effect upon such piles, etc.,

y n sas arnet erica LEWIS R. FERGUSON, OF PHILADELPHIA, PENNSYLVANIA.

REINFORCED CONCRETE FOR MARINE FOUNDATION S.

Specification of Letters Patent.

Patented Nov.; I9, 1918.

application fue@ March 8,4191?. seriai No. 153,373.

T0 all Lo/wm it may concern.'

Be it known 'that I, LEWIS R. FERGUSON, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania., have invented certain new and useful Improvements in Retion is to enhance the durability of such Work, and to protectithe same from the action of the damp salt air which has a most as heretofore constructed.

It has been known that reinforced Concrete piles, cylinders and the like Where exposed to the salt Water lspray and to damp salt air soon crack and spall, such spalling ultimately causing disintegration and failure of the concrete Work. Thisv cracking and spalling has heretofore been attributed to causes other than the true one. I have discovered thatsuch cracking* and spalling is caused by the rapid corrosion or oxidization of the embedded metal reinforcing. I have also discovered that this cracking always starts above the low Water line and is most extensive just above the vhigh Water line; that such spalling and crackingl follows along the lines of the reinforcing rods, and is usually progressive With the corrosion or rusting,r of the metal reinforcing. I have discovered that steel or iron reinforcing bars even. When embedded in concrete piles to a depth of several inches are rapidly corroded in this Way when exposed to damp salt air; and I have further discovered that even when the richest and best made concrete is employed such reinforced piles Will crack and spall almost as rapidly as concrete piles of poorer quality. This disintegrating ac tion of such reinforced concrete piles is not confined to anyparticular locality but is prevalent toa more or less marked extent along both the Atlantic and Pacific coasts, andas consequence all the vpresent reine forced concrete piles exposed .as described to sea or salt air are rapidly deteriorating and failing. i

I have discovered that if the portion of the metal reinforcing which lies within that portion of the concrete pile, cylinder or column that projects above low Water and which is exposed to the action of the damp salt air is formed of' or coated, galvanized or plated with tin, zinc or other suitable non corr'odible or rust resisting metal or metals that will resist the action of the damp salt air but will not prevent. the proper bond or adhesion between the concrete and the metal reinforcingJ embedded therein; the exposed portions of such reinforced concrete will not be liable to crack and spall and will resist the combined action of the salt air and Wash of sea Water Without deterioration, as Well as the submerged portions of the reinforced concrete which are not exposed to the action of air.v y

I have found that the submerged portions 'of reinforced concrete piles are not affected and do not crack and spall ,like the portions of the piles which are above low Water g therefore the submerged portion of the concrete structure needs no special treatment.

Heretofore it has been customary to use ordinary black iron or steel barsextending throughout the concrete pile, cylinder or column for reinforcing' samegvvvhich reinforcing is quickly oxidized by salt air; In carrying' out my invent-ion I preferably protect such reinforcing bars, or at least the portions thereof Within the upper or exposed portion of the pile; which comes above the low Water line, by forming them of a non corrodible metal or galvanizingtinning, plating* or otherwise coating such reinforcement. with a non corrodible or rust resisting metal to prevent corrosion of the reinforcement, and by so doing I indcnitely prolong' the life of such reinforced concrete piles with negligible additional expense.

I will explain the invention as appliedto concrete piles with reference to the accomsubmerged in sea Water, having longitudinally disposed metal reinforcing members embedded therein, the parts of said members in the portions of the pile which Will be eX- posed to the atmosphere when n situ being rust-resisting to prevent spalling of the concrete.

8. A pile adapted to be partly submerged in sea Water, comprising a concrete body, and metal reinforcing members embedded in and extending longitudinally of the pile,

the parts of said membersin the portions of the pile exposed to the atmosphere when n situ being formed of a rust-resisting-metal, substantially as and for the purpose specified.

9. A pile adapted to be partly submerged lin sea Water, comprising a concrete body,

as described.

10. The method of protecting reinforced concrete partly submerged in sea Water and comprising a concrete body with metal reinforcement embedded therein; consisting in making the part of said reinforcement Within the portion of the concrete exposed to the atmosphere rust-resisting to prevent spalling of the concrete.

'lll The method of protecting reinforced concrete partly submerged in sea Water, and comprising a concrete body and metal reinforcement embedded therein; consisting in coating the parts of said reinforcement Within the portion of the concrete body exposed to the atmosphere with rust-resisting material to prevent spalling of the concrete.

12. The method of'protecting reinforced concrete adapted to be partly submerged -in sea Water and comprising a concrete body and metal reinforcement embedded therein; consisting in providing the parts of said reinforcement in the portions of the concretev exposed to the atmosphere With a rustresisting coating to-prevent spalling of the concrete. -A

13. The methodv of protecting reinforced concrete adapted to be partly submerged in sea Water and comprising a concrete body and reinforcement embedded therein; consisting in making the parts of said reinforcement in the portion of the concrete exposed to the atmosphere of rust-resisting metal to prevent spalling of the concrete.

In testimony that claim the foregoing as my own, I aHiX my signature.

LEWS R. FERGUSDN. 

